Clad in red jackets, khaki pants, and workboots, 265 City Year volunteers greet 10,000 students each morning at nearly two dozen Boston schools with cheers and clapping — a grand gesture to show they are welcome. Then the volunteers hit the phones and call those who didn’t show up.

Through another AmeriCorps program, Citizen Schools, 41 corps members act as teaching fellows in high-needs middle schools in Harlem and Brooklyn, where they also help mobilize community partners to volunteer, said Wendy Lee, executive director of Citizen Schools NY.

“Our entire operating model is based on having AmeriCorps service members in schools,” Lee said. If funding were cut, she said, “We’d either have to rethink staffing or rethink the way our model is delivered.”